Mount Pinatubo erupted in 1991 after centuries of dormancy, producing one of the 20th century’s largest eruptions. The volcano lies on Luzon, near the boundaries of Zambales, Tarlac, and Pampanga provinces.
The climactic eruption on 15 June coincided with Typhoon Yunya. Rain from the typhoon loaded the ash column, causing widespread roof collapses and complicating evacuation and rescue operations. More than 800 people died, although monitoring and evacuation saved many more.
Pinatubo injected sulfur dioxide into the stratosphere. The resulting sulfate aerosols reflected sunlight and cooled global average temperatures for several years, with the strongest cooling occurring in the early 1990s. The eruption also created a caldera that later filled with a crater lake.
The volcano had not been recognized as an active threat by many local communities before the unrest began in April 1991. Rapid cooperation among Filipino and international scientists made the evacuation one of volcanology’s major successes.